The present invention relates to a semiconductor device and, more particularly, to a semiconductor protective device formed between an external terminal and an internal circuit to protect the internal circuit from an external surge input.
Input protective diodes, etc., are known as semiconductor protective devices for MOS semiconductor devices such as MOSFETs. However, with semiconductor ICs having bipolar transistors, no semiconductor protective device formed in the IC has been proposed wherein internal elements (internal circuit) are protected against both positive and negative external surge inputs. Therefore, a protective device for a semiconductor device, such as a bipolar IC having a bipolar transistor configuration, is required.